Electrical submersible well pumps (ESP) are often used to pump liquids from hydrocarbon producing wells. A typical ESP includes a pump driven by an electrical motor. Production tubing, which comprises pipes having threaded ends secured together, supports the ESP in most installations. The pump normally pumps well fluid into the production tubing. A power cable extends alongside the production tubing to the motor for supplying power. Installing and retrieving the ESP requires a workover rig to pull the production tubing.
In other installations, coiled tubing supports the ESP. The coiled tubing comprises a continuous length or segment of steel tubing that can be wound on a large reel at the surface before deploying and after retrieving. A power cable with power conductors for supplying power to the motor extends through the coiled tubing. The pump discharges well fluid up the annulus surrounding the coiled tubing. A coiled tubing installation allows the ESP to be installed and retrieved without the need for a workover rig.
Some wells are too deep for a conventional reel of coiled tubing containing a power cable. The weight of the coiled tubing with the power cable can cause the coiled tubing and power cable to part.